* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

a {
  text-decoration: none;
}

ul {
  list-style: none;
}

img {
  border: 0px;
}

/* 清除浮动，解决margin-top塌陷 */
.clearfix:before,
.clearfix:after {
  content: '';
  display: table;
}

.clearfix:after {
  clear: both;
}

.clearfix {
  zoom: 1;
}

.fl {
  float: left;
}

.fr {
  float: right;
}